1. Field of the Invention
The present invention relates to a method and implement for opening a hole in soft material such as rubber, synthetic rubber and synthetic resin.
2. Background Art
Conventionally, as disclosed in the Japanese Patent Laid Open Gazette Hei. 10-274656, there is a well-known device for fully automatically measuring glucose by measurement of whole blood specimen. Also, there is well known an art disclosed in the Japanese Patent Laid Open Gazette Hei. 10-201742 and an art disclosed in the Japanese Patent Laid Open Gazette Hei. 9-131336 as arts of a vacuum blood-collection tube for collecting specimen of blood.
The vacuum blood-collection tube is sealed with a plug made of soft material, such as rubber, so as to keep vacuum state therein. Accordingly, when blood gathered by the vacuum blood-collection tube is sampled to an analysis device automatically, a suction nozzle for sucking blood is brought into the vacuum blood-collection tube. By making diameter of the suction nozzle large, suction time becomes short, whereby time required for one process of analysis can be shorten so much. However, it is required to open a hole of large diameter on the plug so as to make the suction nozzle of so large diameter pass therethrough. As a mean for opening such the hole, conventionally, a method of rotating the nozzle like a drill so as to open a hole, or a punching method that an open-end stick such as a needle (an open-end pipe or the like) is pressed against the plug and pressure is applied thereto so as to penetrate the plug.
However, in the case of boring like a drill, small refuses of soft material disperse and are sucked into the suction nozzle together with blood. On the other hand, in the case of the punching method, a pillar-shaped cut piece of soft material (punched refuse) is separated from the plug and sucked to a tip of the suction nozzle for sampling, whereby the cut piece is conveyed to a blood passage of the analysis device. The punched refuse and the small refuses contaminated in blood are analyzed as foreign substance in analysis route, thereby reducing analysis accuracy. Also, in the blood passage, the punched refuse and the small refuses may be caught in an on-off solenoid valve serving as a volume determination mean for passing a fixed volume, thereby preventing normal opening/closing of the on-off solenoid valve. For preventing this fault, it is required to interpose a filter for removing the punched refuse and the like in a sampling blood supply route, and the filter must be exchanged for every fixed period, whereby it is troublesome.
To cancel this fault, means of opening a plug without generating cut piece by a thin pipe-like needle, such as an injection needle, is also used. With regard to most of the means, the needle serves as a suction nozzle. However, in any case, diameter of the suction nozzle must be small and suction of blood takes a lot of time, thereby constituting a hindrance to rapid analysis.
The plug is not punched out, whereby punched refuse is not generated. However, rounded refuses like those of a rubber eraser are surely generated by friction between the needle and the plug of soft material such as rubber. Since the needle is thin, the needle may be warped when inserted into the plug.
In any case, for making rapid analysis available, it is necessary to keep a measure of size of a diameter of the suction nozzle. Furthermore, for preventing small refuse from being generated, it is preferably to punch out the plug of soft material. Therefore, the purpose of the present invention is to prevent the suction nozzle from sucking punched refuse generated by punching the plug.